The government doesn't want to encourage people on low/medium incomes to bring their families here.

That's why the have increased the salary requirement for the family visa.

Schooling is intentionally expensive so that only wealthier people can educate their children here.

You have to choose:

Live as an adult here, but give your kids a crappy education;
or
Give your kids a better start to their life by staying in your own country.

Your answer will determine how much you value your children's education.